Progesterone/estradiol Ratio in the Late Follicular Phase of Long Gonadotropin-releasing Hormone Agonist Cycles Did Not Differ between Conceived and Not-conceived Women

There is a challenging debate on the effect of premature luteinization on the clinical outcome of ‘controlled ovarian hyperstimulation’ (COH) using long ‘gonadotropin–releasing hormone agonist’ (GnRHa) cycles. Premature luteinization is defined as late follicular progesterone/estradiol ratio more than 1 on the day of human chorionic gonadotropin (HCG) administration. We carried out a retrospective case–control study on 75 conceived cases versus 75 not–conceived control women, receiving long GnRHa cycles in their first cycle of treatment. Premature luteinization developed in 15% of the case group vs. 22% of the control group. Neither the late follicular progesterone/estradiol (P/E2) ratio was significantly different between the two groups, nor the day 3 follicle stimulating hormone (FSH), serum estradiol level on the HCG day, total amount of human menopausal gonadotropins ampoules, number of follicles, retrieved oocytes and transferred embryos. Endometrial thickness was significantly more in the pregnant women than in the non–pregnant group. Premature luteinization seems not to adversely affect the clinical outcome of COH. © 20078 Tehran University of Medical Sciences. All rights reserved. Acta Medica Iranica, 46(1): 71-78; 2008